A (more) complete cheatsheet for Arel, including NamedFunction functions, raw SQL and window functions.
posts = Arel::Table.new(:posts)
posts = Post.arel_table # ActiveRecord
I am passionate about Ruby, but its execution time compared to other languages is extremely high, especially when we want to use more complex algorithms. In general, data structures in interpreted languages become incredibly slow compared to compiled languages. Some algorithms such as ´n-body´ and ´fannkuch-redux´ can be up to 30 times slower in Ruby than Go. This is one of the reasons I was interested in embedding Go code in a Ruby environment.
For those who do not know how shared libraries operate, they work in a similar way as DLLs in Windows. However, they have a native code with a direct interface to the C compiler.
Note Windows uses the DLL system, and in this case, this does not necessarily have to be in native code.
One example is DLLs written in C#, which runs on a virtual machine. Because I do not use windows, I ended up not testing if it is poss
Code is clean if it can be understood easily – by everyone on the team. Clean code can be read and enhanced by a developer other than its original author. With understandability comes readability, changeability, extensibility and maintainability.
A curated list of AWS resources to prepare for the AWS Certifications
A curated list of awesome AWS resources you need to prepare for the all 5 AWS Certifications. This gist will include: open source repos, blogs & blogposts, ebooks, PDF, whitepapers, video courses, free lecture, slides, sample test and many other resources.
function logClass(target: any) { | |
// save a reference to the original constructor | |
var original = target; | |
// a utility function to generate instances of a class | |
function construct(constructor, args) { | |
var c : any = function () { | |
return constructor.apply(this, args); | |
} |
# Sidekiq interaction and startup script | |
commands: | |
create_post_dir: | |
command: "mkdir -p /opt/elasticbeanstalk/hooks/appdeploy/post" | |
ignoreErrors: true | |
files: | |
"/opt/elasticbeanstalk/hooks/appdeploy/post/50_restart_sidekiq.sh": | |
mode: "000755" | |
owner: root | |
group: root |
class Luhn | |
class << self | |
# Write a function that takes one parameter, the credit card number, and returns true or false depending on | |
# whether the number is a valid number. | |
def is_luhn_valid?(card_number) | |
luhn_checksum(card_number).zero? | |
end | |
# write a second function that takes a | |
# number of any length and calculates the Luhn check digit and returns the original |
#!/bin/ruby --verion => 2.0.0-p353
In Ruby, self is a special variable that always references the current object.
Only files under 25 MB can be previewed with the Google Drive viewer.
Google Drive viewer helps you preview over 16 different file types, listed below: